The good news about treating diabetes in felines is that you don’t have to worry about cataracts, renal damage or arthrosclerosis or any of the other things that afflict dogs and humans.
The bad news? Well - read on...
Diabetes is certainly not guaranteed to be found in every fat cat, or even in most cats, as I find diabetes in skinny cats as often as the fat ones, so I think you either get diabetes or you don't, and as I said before, cortisone can unmask it so always look for it.
I have picked up diabetes in felines as young as 4 years old. There were no clinical signs, and they had come in for routine dentals with grotty teeth.
I have had some older cats stop being diabetics once their teeth were removed, but the younger cats seem to stay diabetics and were quite hard to stabilize.
Cat kidneys are so efficient that there will be no clinical signs of increased drinking, because the urine gets concentrated to the point of being sugar syrup. Sometimes they do not even lose weight, as their metabolism can bypass the need for insulin and glucose to a large extent, because it is set for fat and protein metabolism, not carbohydrate metabolism.
Queensland University's Rhett Marshall and Jacqui Rand's Feline Diabetes Mellitus: What Diet Should I Choose and How Do I Manage Problem Cats provides a protocol for diabetic stabilisation using glargine.
They have outlined a protocol for getting these diabetic cats into remission, particularly fat Burmese, and it can involve up to a month in hospital, and uses Glargine Insulin.
It also involves pretty intense monitoring, and they reckon they can get 80 – 90% of cats into remission and off the insulin. So they go home not diabetic, and if you can keep the weight off them and the protein up to them then they should not become diabetic again till they encounter some other stressor.
I have had a Burmese male become diabetic when the owners got a new Burmese male kitten, and we got him back into remission and he stopped being diabetic for a couple of years, then restarted.
As I discussed in the symptoms article, diabetes in felines is one of the reasons I always do a urine test, as it is a sad problem to miss.
A cats’ metabolism is more like cattle than dogs and humans, which means they run on quite low quantities of glucose, though the blood level is maintained at about the same. So the regime for insulin does not need to be nearly so precise as for other animals.
Overdoing the insulin is actually more trouble than under-doing it.
Because with diabetes in felines you only need to approximate the normal blood glucose, you can adjust the insulin dose sufficiently to just get enough glucose to run the brain.
The predisposing signalment is male (neutered) over 8 years old, over 6.8 kgs but Burmese cats can add an extra strong association.
We know that Burmese are more predisposed to diabetes in felines – they have a lipid metabolism problem that seems to be at the core of it and also seems to be related to the ‘friendly’ gene’. In the Australian Mist – which is a breed derived from Burmese – they tracked back the fat and friendly (and diabetic-prone) male cats to a sire called Jelly Bean, a fabulously friendly sire, who produced very friendly offspring.
However they also seem to have a fat gene closely associated as the boys, especially, are huge, get fat and become diabetic quite young. When the Burmese and these aussie mists get fat, they lay down a hard abdominal fat that seems to be associated with diabetes, and they also often weigh over 6.8 kg.
Jelly Bean was a very popular sire because he produced all these super-friendly spotted Burmese-type babies, and we know that friendliness is passed on through the sire’s line genetically, from work done back in 1992 by Sandra McCune. The maternal line obviously does have an influence – genetic and environmental – but it tends to be that friendliness to humans (really - braveness or willingness to investigate novelty) is passed through the paternal line. The maternal genetics contribute more towards friendliness to other cats, and I have found that, harking back to the ‘every Burmese needs to be on prozac or clomicalm’, these Burmese and other very friendly cats seem not to have enough brain space to be friendly to other cats as well.
They tend to be bullies and push other cats around. You do get the occasional very friendly cat who is also a peacemaker (I have only met males like this, but females may exist) but they are pretty rare. It is more common that a cat who is really, really friendly to people that then really just does not like other cats. Either it just does not understand them or is not interested in sharing territory with them.
So the fat gene is widespread because we like these friendly males, so the tendency to get diabetes is quite widespread.
Rhett Marshall has also produced protocols for this intensive method for stabilization of diabetes in felines for owners to do at home.
There is now a sensor that monitors glucose levels every 5 minutes after being inserted subcutaneously and then read remotely so a glucose curve can be done at home.
Watch this space for updates on changes in treatment protocols, but for the moment it is a university-based study. Interestingly, the cats in the study had an average BCS of 5.5 (and varied from 2 – 9) so it is not always a fat cat with diabetes.
To get cats to lose weight (if they have an obesity related diabetes) you have to increase their protein and water. Cats are not fooled by fibre – in the way that dogs, pigs and humans are. You can fill them up with fibre all you like! Cats just keep eating through the fibre to get to their protein requirement and energy requirement.
If you put cats on a very energy-dense (highly palatable) diet, they will gain weight for a while till their metabolism recognizes the need for less food, and they will then eat less. However, they do not lose the weight they have gained without energy restriction, so weight gain tends to be a stepping up process rather than straight line increase.
I use the high fibre diets for the cats who get anal gland problems because despite the fact anal gland evacuation/abscess problems should be rare in cats, in my practice (mainly indoor cats), it is not all that rare and a diet reasonably high in fibre has resolved the problems. The anal glands usually only get in trouble after a round of diarrhoea or constipation, which stops them emptying regularly, under normal poo pressure, and so the cycle starts.
Indoor Burmese seem to me to be the most prone, and very chubby cats as well, because the fat deposits around the gland prevent proper pressure and emptying. Fabulously interesting topic but… If the anal sacs abscess, it usually destroys the glandular lining, and then increasing the fibre seems to keep the other one evacuated.
If a cat has to have its anal glands attended to twice, and despite a high fibre diet, then I would generally talk about removing the glands. Emptying them manually is very rude and painful for the cats, so rather than a regular fight or sedation to clean or clear them, I would recommend removing them. Having said that, I haven’t ever had to do it. If the other side abscesses, then usually all that is required is to flush out the area under anaesthetic, find any bits of lining still around and let them granulate over.
When you want a cat to lose weight you put it on the Atkins diet, so we call it the Catkins diet.
It basically means higher protein and water, and is thus the diabetic diet.
So 46% protein in the special dried food for diabetics – Hills and Waltham prescription food (wet and dried), or pretty much any wet food with real chicken and lamb on the side. I’ve managed quite a lot of diabetics with diet alone – just feed meat and diabetic dried for the extra vitamins and minerals, or meat and Vitamax greyhound supplement. As long as you can stop them going into ketosis, and while the kidneys are still functioning, they can pee glucose for a long time.
You will get the occasional infection, renal or bladder (haematuria), or skin maybe, because of the extra glucose in the serum etc, but with antibiotics they are usually fine. I had one cat go for five years on diet alone because the owner refused to give it insulin, and even though she had severe senile lens degeneration, so she looked like she had cataracts, the eye pathologist said there was no cataract formation there histopathologically.
So diet alone is a useful management tool, and the high protein diet should be instigated at the start, so any insulin required is titrated with the proper diet alongside, or you will have to adjust the insulin later.
If you are only using diet, you have to monitor the urine for ketones. As soon as they have ketones, they need insulin because they cannot cope with that on their own.
What you will see if a kidney infection is present.